5) The Big Bad Of Suicide Squad 2
Despite the mauling Suicide Squad received from critics, the fact that it has now grossed over $600 million worldwide makes a sequel very likely. It remains to be seen which villains end up taking centre stage in that, but Warner Bros. will have surely taken notice of the complaints levelled at both the lack of screentime for The Joker and the pathetic excuse for big bads in the form of Enchantress and her brother. So, with that in mind, why not make the Clown Prince of Crime the foe that Task Force X needs to bring down? He would be outgunned, yes, but that may not matter.
After all, The Joker could very well put together a team of his own (something which would lead to the introduction of more great characters from the comic books), while making him the threat that Amanda Waller needs to take down might open the door to her having to enlist Batman to help stop the villain. The mid-credits scene for Suicide Squad obviously revealed that she knows it’s Bruce Wayne under the mask, and assuming Ben Affleck would say yes, pairing up the members of Task Force X with Batman to fight The Joker would be a guaranteed box office hit.